This　paper　aims　to　understand　the　effect　of　mainshock-aftershock　earthquake　sequences　on　the　seismic　performance　of　multi-story　concentrically　braced　frames　(CBFs)　equipped　with　shape　memory　alloy　(SMA)　friction　damping　braces　(SMAFDBs),　based　on　a　comparison　with　those　equipped　with　buckling-restrained　braces　(BRBs).　The　SMAFDB　is　a　serial　connection　of　SMA　damper　and　friction　damper.　The　friction　damper　starts　to　slip　and　serves　as　the　＂fuse＂　element　to　protect　the　SMA　damper　under　destructive　earthquake　events.　Ten　ground　motion　records　corresponding　to　the　maximum　considered　earthquake　(MCE)　hazard　level　are　defined　as　the　mainshock　input,　and　the　aftershock　input　is　generated　by　appropriately　scaling　the　mainshock　input　to　four　seismic　hazard　levels.　To　achieve　a　fair　comparison,　the　considered　CBFs　are　first　designed　to　exhibit　identical　mean　height-wise　peak　interstory　drift　ratios　under　the　design-basis　earthquake　(DBE)　ground　motions.　Then,　these　two　frames　are　subjected　to　four　suites　of　mainshock-aftershock　earthquake　sequences　and　their　seismic　responses　are　compared　against　each　other.　It　indicates　that　both　the　peak　and　residual　interstory　drift　ratios　of　the　SMAFDB　frame　(SMAFDBF)　are　smaller　than　that　of　the　BRB　frame　(BRBF)　on　average　during　the　aftershock　earthquakes,　which　is　found　primarily　attributed　to　the　fact　that　the　former　suffers　from　smaller　post-mainshock　residual　deformation.　The　higher　seismic　capacity　of　the　SMAFDBF　over　the　BRBF　is　also　confirmed　by　conducting　fragility　analysis.　Finally,　the　recentering　capacity　under　aftershock　earthquakes　are　analyzed　for　both　frames,　based　on　the　maximum　residual　interstory　drift　ratios.